ASVAB CampAngles and Lines flashcards
8 cards with the formulas, rules and traps from this lesson. Answer in your head, then flip to check.
Term · 1/8
How are angles classified by measure?
Acute: more than 0° and less than 90°. Right: exactly 90°. Obtuse: between 90° and 180°. Straight: exactly 180°. Reflex: between 180° and 360°.
Term · 2/8
Complementary vs. supplementary angles?
Complementary angles total 90°; supplementary angles total 180°. The complement of 34° is 56°, and its supplement is 146°. Memory aid: C comes before S, as 90 comes before 180.
Fact · 3/8
Two lines cross: how are the four angles related?
Opposite (vertical) angles are equal, and side-by-side angles form linear pairs that total 180°. If one angle is 47°, the four angles are 47°, 133°, 47° and 133°.
Fact · 4/8
Angle totals along a straight line and around a point?
Adjacent angles filling a straight line total 180°; non-overlapping angles that surround a point total 360°. Angles of 100°, 75°, 120° and x around a point give x = 65°.
Rule · 5/8
Parallel lines cut by a transversal: which angle pairs are equal?
Corresponding angles, alternate interior angles and alternate exterior angles are all equal. If one angle of a corresponding pair is 64°, its partner is also 64°.
Common trap · 6/8
Are same-side interior angles equal when the lines are parallel?
No. Same-side (consecutive) interior angles are supplementary, adding to 180°. If one is 105°, the other is 75°.
Fact · 7/8
Parallel lines and a slanted transversal: how many angle sizes appear?
Only two: four equal acute angles and four equal obtuse angles, with acute + obtuse = 180°. If one angle is 52°, every angle is either 52° or 128°.
Common trap · 8/8
Can you assume lines are parallel or perpendicular from a drawing?
No; figures may not be to scale. Trust only stated facts and markings: a small square for 90°, matching arrows for parallel lines, tick marks for equal parts. Equal vertical angles never prove lines parallel.